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Pluto? Try 'Trans-Neptunian Object.'

STOCKS GET THROWN off the S&P 500 and
socialites get knocked off the A list, but never in the history of the
solar system has there been a demotion like this: astronomers are taking
steps to delete Pluto from the list of planets. No, the smallest and
(usually) most distant of the nine planets, discovered in 1930, hasn't
decamped to Alpha Centauri. Rather, some astronomers believe that Pluto
never deserved to be ranked with the likes of Jupiter, Saturn and Earth
in the first place. As soon as this week or as late as this spring, the
International Astronomical Union is expected to vote to reclassify Pluto
as a ""minor planet,'' of which there are close to 10,000. Or it could
be reclassified as a ""trans-Neptunian object,'' or TN-1. That's a fancy
way of saying Pluto is just another icy rock in the sea of asteroids
beyond Neptune called the Kuyper Belt.

Pluto just doesn't fit the planetary mold. It's smaller than
seven moons in the solar system, including Earth's. And while the orbits
of real planets are almost circles, Pluto's is so goofy that it
frequently swings closer to the sun than Neptune does. It is neither
rocky like four planets nor gassy like the other four. The
reclassification makes scientific sense and ""is not a demotion,''
insists Brian Marsden of the Harvard-Smithsonian Center for
Astrophysics. ""It's an honor.'' Tell that to the legions of
schoolchildren who have learned ""My Very Educated Mother Just Served Us
Nine Pizzas.'' Or to astrologers: Pluto, the sign of disruption, rules
Scorpio. If Pluto isn't a planet, then a lot of people have a different
future.